Pros:

Perfect for playing certain modes offline
Bots don't act like idiots (though the special infected do seem smarter...)

Cons:

Considered cheats, causing disabled achievements

Conclusion:

Pretty good, I'll add more as I go on.

Pros:

Really addicting to use
Great animation
No glitches in the design

Cons:

Knife could use a damage script

Conclusion:

Love it, keep up the good work

Pros:

Music fits perfectly, even better than Midnight Riders (sorry)
So Far Away fits great when someone dies.
Really like the guitar skins

Cons:

Can't think of any

Conclusion:

Flawless addon